diff --git a/pom.xml b/pom.xml
index f0608e1..0a0a07f 100644
--- a/pom.xml
+++ b/pom.xml
@@ -14,7 +14,6 @@
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 		<project.scm.id>github</project.scm.id>
 		<repoUrl>https://repo.icatproject.org/repo/</repoUrl>
-		<luceneVersion>5.3.0</luceneVersion>
 	</properties>
 
 	<repositories>
@@ -62,12 +61,6 @@
 
 	<dependencies>
 
-		<dependency>
-			<groupId>org.apache.lucene</groupId>
-			<artifactId>lucene-core</artifactId>
-			<version>${luceneVersion}</version>
-		</dependency>
-
 		<dependency>
 			<groupId>javax</groupId>
 			<artifactId>javaee-api</artifactId>
diff --git a/src/main/java/org/icatproject/icat/client/ICAT.java b/src/main/java/org/icatproject/icat/client/ICAT.java
index 5bcf592..2986acd 100644
--- a/src/main/java/org/icatproject/icat/client/ICAT.java
+++ b/src/main/java/org/icatproject/icat/client/ICAT.java
@@ -47,8 +47,6 @@
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.message.BasicNameValuePair;
 import org.apache.http.util.EntityUtils;
-import org.apache.lucene.document.DateTools;
-import org.apache.lucene.document.DateTools.Resolution;
 import org.icatproject.icat.client.IcatException.IcatExceptionType;
 import org.icatproject.icat.client.Session.Attributes;
 import org.icatproject.icat.client.Session.DuplicateAction;
@@ -556,11 +554,10 @@ String searchInvestigations(String sessionId, String user, String text, Date low
 				gen.write("text", text);
 			}
 			if (lower != null) {
-				// TODO Remove DateTools as it is from a Lucene library!
-				gen.write("lower", DateTools.dateToString(lower, Resolution.MINUTE));
+				gen.write("lower", roundMinute(lower, 0));
 			}
 			if (upper != null) {
-				gen.write("upper", DateTools.dateToString(upper, Resolution.MINUTE));
+				gen.write("upper", roundMinute(upper, 59999));
 			}
 			if (parameters != null && !parameters.isEmpty()) {
 				writeParameters(gen, parameters);
@@ -609,10 +606,10 @@ private String searchDocuments(String target, String sessionId, String user, Str
 				gen.write("text", text);
 			}
 			if (lower != null) {
-				gen.write("lower", DateTools.dateToString(lower, Resolution.MINUTE));
+				gen.write("lower", roundMinute(lower, 0));
 			}
 			if (upper != null) {
-				gen.write("upper", DateTools.dateToString(upper, Resolution.MINUTE));
+				gen.write("upper", roundMinute(upper, 59999));
 			}
 			if (parameters != null && !parameters.isEmpty()) {
 				writeParameters(gen, parameters);
@@ -665,10 +662,10 @@ String searchDatasets(String sessionId, String user, String text, Date lower, Da
 				gen.write("text", text);
 			}
 			if (lower != null) {
-				gen.write("lower", DateTools.dateToString(lower, Resolution.MINUTE));
+				gen.write("lower", roundMinute(lower, 0));
 			}
 			if (upper != null) {
-				gen.write("upper", DateTools.dateToString(upper, Resolution.MINUTE));
+				gen.write("upper", roundMinute(upper, 59999));
 			}
 			if (parameters != null && !parameters.isEmpty()) {
 				writeParameters(gen, parameters);
@@ -711,8 +708,8 @@ private void writeParameters(JsonGenerator gen, List<ParameterForLucene> paramet
 			if (parameter.getStringValue() != null) {
 				gen.write("stringValue", parameter.getStringValue());
 			} else if (parameter.getLowerDateValue() != null && parameter.getUpperDateValue() != null) {
-				gen.write("lowerDateValue", DateTools.dateToString(parameter.getLowerDateValue(), Resolution.MINUTE));
-				gen.write("upperDateValue", DateTools.dateToString(parameter.getUpperDateValue(), Resolution.MINUTE));
+				gen.write("lowerDateValue", roundMinute(parameter.getLowerDateValue(), 0));
+				gen.write("upperDateValue", roundMinute(parameter.getUpperDateValue(), 59999));
 			} else if (parameter.getLowerNumericValue() != null && parameter.getUpperNumericValue() != null) {
 				gen.write("lowerNumericValue", parameter.getLowerNumericValue());
 				gen.write("upperNumericValue", parameter.getUpperNumericValue());
@@ -851,10 +848,10 @@ String searchDatafiles(String sessionId, String user, String text, Date lower, D
 				gen.write("text", text);
 			}
 			if (lower != null) {
-				gen.write("lower", DateTools.dateToString(lower, Resolution.MINUTE));
+				gen.write("lower", roundMinute(lower, 0));
 			}
 			if (upper != null) {
-				gen.write("upper", DateTools.dateToString(upper, Resolution.MINUTE));
+				gen.write("upper", roundMinute(upper, 59999));
 			}
 			if (parameters != null && !parameters.isEmpty()) {
 				writeParameters(gen, parameters);
@@ -943,4 +940,13 @@ public String list(String sessionId, String path) throws IcatException {
 		}
 	}
 
+	/**
+	 * @param date   Date to round down to the minute
+	 * @param offset Number of ms to be added to the returned value
+	 * @return Rounded date, converted to ms with offset applied
+	 */
+	private long roundMinute(Date date, long offset) {
+		return (date.getTime() / 60000) * 60000 + offset;
+	}
+
 }
diff --git a/src/test/java/org/icatproject/icat/TestIcatClient.java b/src/test/java/org/icatproject/icat/TestIcatClient.java
index 43de411..6f0a160 100644
--- a/src/test/java/org/icatproject/icat/TestIcatClient.java
+++ b/src/test/java/org/icatproject/icat/TestIcatClient.java
@@ -106,7 +106,7 @@ public void testSession() throws Exception {
 
 	@Test
 	public void testInfo() throws Exception {
-		assertTrue(icat.getVersion().startsWith("5.0."));
+		assertTrue(icat.getVersion().startsWith("5.1."));
 	}
 
 }